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A075815
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Palindromic odd composite numbers with an odd number of prime factors (counted with multiplicity).
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0
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99, 171, 333, 343, 363, 555, 575, 595, 747, 777, 909, 969, 1001, 1221, 1331, 1551, 1771, 3333, 3553, 5335, 5445, 5555, 5665, 5775, 5885, 5995, 7337, 7557, 7667, 7777, 7887, 9009, 9339, 9559, 9669, 9779, 9889, 11211, 11511, 11711, 11811, 12121
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| 5445=3^2*5*11^2 and 5555=5*11*101 are palindromic, odd, composite and have an odd number of prime factors.
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MAPLE
| test := proc(n) local d; d := convert(n, base, 10); return ListTools[Reverse](d)=d and type(numtheory[bigomega](n), odd) and not isprime(n); end; a := []; for n from 1 to 13000 by 2 do if test(n) then a := [op(a), n]; end; od; a;
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CROSSREFS
| Cf. A046389.
Sequence in context: A185498 A126230 A055164 * A075814 A157947 A097599
Adjacent sequences: A075812 A075813 A075814 * A075816 A075817 A075818
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KEYWORD
| nonn,base
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AUTHOR
| Jani Melik (jani_melik(AT)hotmail.com), Oct 13 2002
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EXTENSIONS
| Edited by Dean Hickerson (dean.hickerson(AT)yahoo.com), Oct 21 2002
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